Source: common sense. Where else could Mercedes driver have forced the Tesla out of his lane? Look at image and give us another possibility.
Fine, lets do that.
Lets start with the flaws in your hypothesis. You propose that the Tesla was under high acceleration and stubbornly "fighting" for position right up until he crossed over (for an unknown reason) at point B and impacted the Honda. You mention the word "physics" and you arbitrarily decide that the Tesla was traveling at 80mph for purposes of your calculation (500ft @ 80mph = 4.6 seconds or whatever).
Using the word "physics" doesn't mean that you then get to ignore actual physics. So lets start with the physics of the impact. The photographs, while not conclusive, are in fact quite consistent with an impact speed of ~80mph. A
combined speed of 80mph anyways (each car traveling @ ~40mph).
The photos are not even remotely consistent with a combined impact of say, 120mph. At that sort of combined speed it seems more likely that the Honda would have been ripped apart instead of just mashed and the Tesla likely would have been as well.
Here is a video showing multiple offset collisions at an 80mph combined speed. Pay particular attention to the large car vs small car scenario at the 1:40 mark and you will see damage much like we see in this crash. Keep in mind that the Tesla is even more formidable than the Camry shown in this video, as it is both much more heavy and Tesla claims the highest structural rigidity of any car in the world -
So given that the visible damage is very consistent with a combined speed of ~80mph (or possibly lower considering what a tank the Model S is, while the Honda was 20 years old and comparatively fragile), is it your contention that the Honda was parked on the roadway?
Otherwise, the impact energies are subject to the laws of physics, in which case kinetic energy is calculated E=1/2mv^2.
Because the equation relies on the
square of velocity, impact energies ramp up quickly with speed. Ignoring the units, 1/2*100*50^2 = 125,000 "whatevers" while increasing the velocity in the equation to 60 results in a total of 180,000 "whatevers" which is almost 50% more "whatevers" just moving the velocity from 50 to 60.
There is a reason that cars are not tested at combined impact velocities of ~140mph (which is what you would expect on a typical highway). The reason is that cars that are involved in a head on collision at that speed leave a smear of debris and gore as opposed to recognizable vehicles.
So your hypothesized scenario of the Tesla driver grimly fighting for position almost to the point of impact appears to be ignoring the lack of damage corresponding to high combined impact speeds.
Second, the accident photos show skid marks which clearly seem to be associated with the Tesla. If they are, they indicate that the Tesla was moving to the
right at the time of impact (back into the center lane) and then curved back to the left following the impact as the torsional energies from the impact, and the implosion of the left side of the Tesla forced the car back into the oncoming lane and then opposite guardrail.
Here is a link to the photo, and note the skid marks in the center lane on the right side. I believe they are from the Tesla. I'm sure the actual investigators can determine if they are. If so, the car was moving pretty aggressively to the right at the time of impact, not to the left as you'd have us believe.
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That indicates that the Tesla in fact moved into the oncoming lane well before point B on your photo, making your 4.6 second estimate moot. In fact, if the Tesla had lost control shortly after point A on your photo, possibly as the Merc intentionally or unintentionally guttersniped him, forcing him to move to the left and react while at highway speeds, the natural result would have been to dip into the oncoming lane and then struggle to not hit the guardrail as the road curved towards him.
You see him fighting these forces and drifting unavoidably to the left, while I see him fighting these forces and winning before making a hard move to the right prior to impact. My scenario has him crossing the middle lane perhaps only a third of the way past point A and nearly hitting, or brushing against, the guardrail before beginning to fight his way back into the center lane shortly before point B.
But crucially, I also see the Tesla decelerating prior to impact. With his deceleration starting sooner than the Honda's (the Honda would not have been aware of a problem till relatively late in the process) there is no reason to suppose that he was going faster than the Honda at all, and the combined speed is likely much closer to 80 than it is to 120. Your scenario starts with the Tesla doing 80 at impact and leaves little room for the Honda to be moving at all.
The way I see it, the evidence is supportive of the idea that the Merc failed to yield and was being forced onto the shoulder while the Model S was being forced into the middle lane. If the Merc was pulling past the Tesla while crabbing the shoulder he might well have made a hard move into the lane when he thought he had passed the Tesla, due to an understandable fear of running into the brush next to the shoulder.
By this point we are maybe a third of the way from point A to point B and the Merc "cuts off" the Tesla who might be decelerating and might have hit the brakes heading into the turn. Suddenly hitting the brakes in a turn while at highway speeds is a classic way to lose control of the vehicle, and the natural motion of the car combined with the driver tending to the left to avoid the Merc could well have resulted in an uncontrolled lane departure at that point.
Do I know this is what happened? No, I am not a trained accident investigator, and I lack the logs from the Tesla and analysis of the skid marks and impact speeds that would help properly model the accident. It's an opinion based on my own (potentially flawed) interpretation of the evidence that we have.
But I do know that your hypothesis is almost entirely unsubstantiated and speculative in the extreme. The idea that these cars were drag racing is nothing but pure gossip based on a highly shaky interpretation of an incomplete set of "facts". If the police make an arrest it wont be because they relied on so called evidence generated by this forum. They will look at vehicle logs, witness statements and their own reconstruction of the accident based on actual science instead of amateur musings that are trying to pass themselves off as informed analysis.
